1. Field of the Invention
This invention relates generally to a substantially non-irritating oral composition, and more particularly, to a non-irritating oral composition exhibiting high foaming properties.
2. The Prior Art
Sodium lauryl sulfate (SLS) is a widely used surfactant in oral compositions. Surfactants, and particularly anionic surfactants such as sodium lauryl sulfate (SLS) are an essential ingredient of oral compositions and serve as a solubilizing, dispersing, emulsifying and wetting agent for the other ingredients present in the dentifrice and is especially effective in solubilizing the flavor present. A cosmetic effect of the presence of the surfactant is that it promotes foaming of the oral composition. Oral compositions with strong foaming ability are preferred by consumers since the foaming provides the perception that the oral composition cleans effectively only if it foams well.
The incorporation of anionic surfactants such as SLS in oral compositions such as dentifrices is known to cause adverse reactions to oral tissue as shown in R. C. Caldwell and R. E. Stallard, A Textbook of Preventive Dentistry, 196, W. B. Saunders (1977); L. J. Guarnieri, IADR, Abstract No. 661 (1974); L. J. Guarnieri, Thesis, University of Indiana (1970).
One example is gingival irritation. It is also believed that SLS is responsible for sloughing of the oral mucosa.
The art therefore has been seeking a non-irritating alternative surfactant to SLS as a surfactant for dentifrices.
U.S. Pat. Nos. 4,690,776 and 5,041,280 disclose the use of the anionic surfactant sodium lauryl sulfoacetate in dentifrice formulations. However, the problem of oral irritation due to the presence of anionic surfactants in the dentifrice is not mentioned in the aforesaid patents.
According to the published literature; namely, "Surfactants in Cosmetics (Marcel Dekker), Vol. 16, Ch. 10, Pages 303-304 (1985), sodium lauryl sulfoacetate is of comparatively little importance commercially in oral hygiene products. According to this publication, although the use of sodium lauryl sulfoacetate has been proposed as a foaming agent in dentifrices and other dental preparations, it is not considered as an organoleptically acceptable product for commercial applications.
Attempts to use commercially available sodium lauryl sulfoacetate as a surfactant in oral products such as dentifrices indicate the problem of a bitter taste associated with the presence of the compound in the oral product. Further, compared to SLS, dentifrices employing sodium lauryl sulfoacetate as the surfactant exhibit inferior foaming properties.